When the pressure changes from 1.21 atm to 2.52 atm, the volume changes from 3.75 l to 1.72 l and the temperature changes from 293 k to _ k

Answer is 280 K

Explanation:

Let's assume that the gas is an ideal gas.

Then we can use combined gas law,

 PV/T = k (constant)

Where, P is the pressure of the gas, V is volume of the gas and T is the temperature of the gas in Kelvin.

For two situations, we can use 

P₁V₁/T₁= P₂V₂/T₂

P₁ = 1.21 atm  

V₁ = 3.75 L  

T₁ = 293 K

P₂ = 2.52 atm

V₂ = 1.72 L

T₂ = ?

From substitution,

  1.21 atm x 3.75 L / 293 K = 2.52 atm x 1.72 L / T₂

                                      T₂ = (2.52 atm x 1.72 L x 293 K) / (1.21 atm x 3.75 L)

                                      T₂ = 279.9 K

                                      T₂ = 280 K

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.